INVESTIGADORES
SCHULZ Erica Patricia
artículos
Título:
Spatial arrangements of particles with different mobility tendencies in a model glass-former.
Autor/es:
D. MALASPINA; E.P. SCHULZ; M.A. FRECHERO; G. A. APPIGNANESI
Revista:
Physica A
Editorial:
ELSEVIER
Referencias:
Año: 2009 p. 3325 - 3333
ISSN:
0378-4371
Resumen:
The use of the isoconfigurational method has enabled one to determine the existence of
particles with high and low dynamic propensity (tendency to be mobile) and particles with
preferred directionality for motion (directional particles) in supercooled liquids. On the
other hand, dynamical studies have shown that the relaxation of such systems evolves by
means of rapid crossings between metabasins of the potential energy surface (a metabasin
being a group of mutually similar, closely related structures which differ markedly from the
ones belonging to other metabasins), as collectively relaxing units (d-clusters) take place.
Here we determine the spatial arrangements of such particles in a model three dimensional
glass-forming system. We show that both the highest and the lowest propensity particles
form compact clusters, which are separated from each other by the high directionality
particles. The particles of this interfacial region seem to behave as to help make room for
the enhanced (expansion) movement of the high propensity cluster and to keep the local
density constant. Finally, we also find that only the high propensity particles (but not the
directional ones) exhibit a great tendency to take part in d-cluster events